A Buried Gas Pipeline Leakage Model

Unlike the hydrodynamic model used in the current popular numerical simulation of buried gas pipeline leakage, this paper adopts the Darcy equation of underground seepage, mass balance equation, and equation of state of gas to establish a buried gas pipeline leakage model. Geometrically, the established model is a soil cylinder with the ground as the top surface and the vertical line through the pipeline leakage point as the axis. Due to the axial symmetry, the three-dimensional buried pipeline leakage model is expressed as a two-dimensional mathematical problem. A series of key concepts about the hydrodynamic model of buried pipeline leakage and its solution are presented. A comprehensive description of the physical process (pressure and flow rate) of buried gas pipeline leakage is provided through numerical examples. Quantitative analysis was conducted on the relevant structural parameters of the model and relations of leakage flow rate with related factors of leakage. By providing a comprehensive and quantitative understanding of buried gas pipeline leakage, this paper proposes a flow rate formula and an estimation formula of leak orifice equivalent diameter of leaking buried pipelines, and provides a theoretical and data processing framework for experimental study of buried gas pipeline leakage.